mikuni swap keinen what jets

blaster man1

Member
Jul 30, 2014
125
7
38
41
scotland
hi nead help working out jet sizes have changed my carb to keinen 28mm was using stock carb mikuni 26mm standard pilot jet with 270 main jet can us give me info on wat size jets to start with
 
There was a thread somewhere with what I think was like a conversion chart/comparison. Cant seem to find it at the moment, but you can go through threads and look what others are running with the same mods and that should get you close.
 
Last edited:
check these threads to see if anyone has posted info on the 28mm K,
with similar mods to yours (pipe/filter/airbox lid, ect.)

http://www.blasterforum.com/threads/what-jets-are-you-using.28981/

http://www.blasterforum.com/threads/jetting-numbers-the-solution.17259/


edit: here's one i found in those threads.....

http://www.blasterforum.com/threads/what-jets-are-you-using.28981/#post-342448

1) What type of exhaust do you have? Toomey

2) What type of airfilter do you have? Foam, cheapie aftermarket

3) Are you a)running a stock airbox with lid stock airbox with NO lid c) Stock airbox with vents d) no airbox at all What happened to b)?

4) What is your elevation? 4100 Ft

5) What size pilot jets are you using? 45

6) What size main jets are you using? 162

7) What is your Bore Size? .040 over stock

8) Do you have a port job? no

9) What kind of carb? Keihin PWK28

10) What size is your carb? 28mm

*********************************************************


although the toomey calls for a 310-330 main in the stock carb.
so that 162 listed above will be way too large for you if you had been running a plug chop confirmed 270


i'd try......

45 pilot, confirm with the airscrew
http://www.blasterforum.com/threads/adjusting-your-airscrew-pilot-jet.51060/

150 main to start and plug chop to confirm main jetting
http://www.blasterforum.com/threads/how-to-plug-chop.53237/
 
my mods are full dmc alien exhaust boysen duel stage reeds no-toil air filter with no lid pwk 28mm carb elivation is sea level pre-mixing oil at 32-1
 
my mods are full dmc alien exhaust boysen duel stage reeds no-toil air filter with no lid pwk 28mm carb elivation is sea level pre-mixing oil at 32-1


i'd buy.....
45/48/50 pilots
145/148/150 mains

check/set float height first:
http://www.blasterforum.com/threads/float-heights-and-how-to-adjust-them.50565/

use the airscrew guide i posted above to find the correct pilot,

start with the needle on middle clip position, if it bogs in the mids no matter the clip position, you'll need to order a CEL needle from ebay or carb parts warehouse, (99% of us keihin users have had to change the needle to the CEL for lower elevations like yours, or the DGH for higher elevations)

then start with the large main jet and plug chop down
 
  • Like
Reactions: blaster man1
is this the needle
KEIHIN JET NEEDLE CEL 17.02 N427-48CEL and thanks for info

carb parts warehouse lists a N427 - 46 xxx (xxx = cel) as the needle # for a 28mm pwk.....
http://www.carbparts.com/keihin/pwk28parts.htm

not sure what the "48" vs. "46" means ?
xcbob on ebay lists the 48 as for 34mm and larger carbs ?

i'd just call and order from carb parts warehouse, (216) 635-1099
to be 100% sure.
but order everything together and only pay the $7 shipping once for everything
 
thanks dont know what i would do without this forum and the menbers. it has saved me a large fortune and the info is spot on the maker ov this site should be proud
 
do you have the exact info on the needle

yes, exactly what carb parts warehouse lists for a pwk 28mm.....N427 - 46xxx (xxx = CEL in this case)

sudco.com has the same #'s
N427 - 46xxx for pwk 28's
N427 - 48xxx for 33mm + carbs

http://www.sudco.com/pwk.html

there has to be a difference between the 46 and 48 #
you need a N427 - 46xxx, not 48
 
CEL and DGH are waaaaaaaaay too long for a 28 PWK. You need something like a JJH.


length could be what the 46/48 difference is between the 28 and larger carb needles ?
but if you have experience with the JJH in a 28, then JJH it is ?
 
My set-up PKW28 jetting was... 155 main 45 pilot and JJH needle with clip in the middle ,3.5 slide and 19 mm float setting.